Load box rail trims in a truck are usually blow molded or are extruded aluminum. Blow molding process is expensive, time consuming, and the load box rail trims made can have varying wall thicknesses that are hard to control. In addition, the cross sections of the load box rail trims made from blow molding have closed loop and thus fasteners and metal bracket are required to connect the rail trims to the load box of the truck. The inventor of this application has recognized a need for load box rail trims that improve upon and advance the design of known load box rail trims,